In semiconductor devices, high-K dielectrics are frequently included as a part of or underneath gate elements to decrease device size and increase device performance. The use and effectiveness of high-K dielectrics in devices such as transistors, gates, etc. may be impacted by exposing these dielectrics to oxygen. In these cases, oxygen may diffuse into these high-K dielectrics, causing the threshold voltage and the effective work function of the system to deviate from the desired design values. Some semiconductor devices limit the diffusion of oxygen into high-K dielectrics by placing a blocking layer of excess high-K material or silicon nitride on the sides of the gate to act as a shield. However, in these methods, oxygen may still diffuse into the high-K dielectrics by saturating the blocking layer, diffusing through the blocking layer or diffusing into the gate from below (e.g., through the substrate or other lower layer(s)).